Bottom plate of liquid-cooled battery pack and box body thereof

Abstract

The utility model relates to the technical field of battery boxes, and discloses a bottom plate of a liquid-cooled battery pack and a box body of the liquid-cooled battery pack, the bottom plate comprises a bottom plate main body, a front panel, a rear panel, a left side beam and a right side beam, the front panel, the rear panel, the left side beam and the right side beam are fixed on the upper surface of the bottom plate main body, and a cavity enclosed by the bottom plate main body and the front panel and the rear panel is used for accommodating a battery cell module; the bottom plate body comprises a middle bottom plate and side bottom plates located on the two sides of the middle bottom plate, and the side bottom plates are fixedly connected with the left side beam and the right side beam. The interiors of the middle bottom plate and the side bottom plates are hollow cavities, and the hollow cavities are used as liquid cooling areas of the battery pack; a plurality of reinforcing beams are arranged on the bottom plate main body along the length direction of the bottom plate main body and are arranged in the liquid cooling area of the bottom plate main body; a fixing hole is formed in the reinforcing beam, and the opening direction of the fixing hole faces the side away from the cavity; a cooling flow channel is arranged in the liquid cooling area, and plugging blocks are arranged at the two ends of the bottom plate body in the length direction. In practical application, the space occupied by the battery pack in the vehicle is effectively reduced, and the utilization rate of the space in the vehicle is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of battery boxes, in particular to a bottom plate of a liquid-cooled battery pack and a box body thereof. Background Art

[0002] In modern electric vehicles and energy storage systems, the battery pack, a core component of energy storage, has a significant impact on overall safety, stability, and maintenance. The commonly used battery pack mounting strategy currently in use places mounting points on opposite sides of the pack, connecting the pack to the vehicle chassis or frame via metal brackets and fasteners such as bolts. While this arrangement meets basic installation requirements to a certain extent, in practice, there are several drawbacks: The side-mounted design requires a certain clearance between the battery pack and the vehicle structure to accommodate the mounting components. This occupies valuable space within the limited vehicle body, compressing the available battery pack volume, indirectly impacting battery capacity and vehicle range, and limiting the space available for other critical components, such as the cooling system and electronic control system. Furthermore, the battery pack is supported solely by mounting points on both sides, resulting in a weak overall structural strength. This can easily cause distortion and deformation in side collisions or severe jolts, damaging the internal structure and compromising performance.

[0003] To address the above issues, this solution provides a liquid-cooled battery pack case, which not only reduces the overall space occupied by the battery pack, but also enhances the structural strength of the battery pack to ensure the performance of the battery pack. Summary of the Invention

[0004] The utility model is intended to provide a base plate of a liquid-cooled battery pack and a box body thereof, so as to reduce the space occupied by the battery pack in the vehicle body and enhance the overall structural strength of the battery pack.

[0005] To achieve the above-mentioned object, the present invention adopts the following technical solution: a bottom plate of a liquid-cooled battery pack, comprising a bottom plate body and front and rear panels and left and right side beams fixed to the upper surface of the bottom plate body, the cavity surrounded by the front and rear panels and the left and right side beams below and being used to accommodate battery cell modules, the bottom plate body comprising a middle bottom plate and side bottom plates located on both sides of the middle bottom plate, the side bottom plates being connected and fixed to the left and right side beams; the interiors of the middle bottom plate and the side bottom plates are both hollow cavities, which serve as liquid cooling zones of the battery pack; a plurality of reinforcing beams are provided on the bottom plate body along its length direction, the reinforcing beams are arranged in the liquid cooling zone of the bottom plate body, the reinforcing beams are connected to the inner walls of the upper and lower sides of the bottom plate body along the thickness direction, the reinforcing beams on the side bottom plates are arranged on the side of the side bottom plate away from the middle bottom plate, and are located outside the liquid cooling zone; fixing holes are opened on the reinforcing beams, the opening direction of the fixing holes facing the side away from the cavity; a cooling flow channel is provided in the liquid cooling zone, and sealing blocks are provided at both ends of the bottom plate body in the length direction.

[0006] The principles and advantages of this solution are:

[0007] 1. Compared with the side fixing strategy of the battery pack in the prior art, this solution fixes the bottom plate to the frame crossbeam below it by setting fixing holes on the bottom surface of the bottom plate. The fixing holes are distributed on the bottom plate as the fixing points of the battery pack, that is, the fixing point of the battery pack is located at the bottom of the battery pack. On the one hand, it reduces the side volume required for the fastening components to be installed on the side, reduces the battery pack's occupation of the vehicle's Y-direction space, and effectively avoids the battery pack's interference with the installation of other components or systems. On the other hand, the volume of the battery pack that can accommodate the battery cell module is increased, which increases the overall energy of the battery pack, increases the volume energy density, and improves the vehicle's endurance.

[0008] 2. In the prior art, the battery pack is only connected and fixed to the vehicle frame on both sides, and its bottom is in a suspended state, resulting in low overall structural strength of the battery pack. When encountering a side collision or severe bumps, the battery pack, which is only supported by the two sides due to the lack of sufficient torsional rigidity and lateral stability, is prone to twisting and deformation, affecting the uniform force between the battery cells. In this solution, a reinforcing beam is provided on the main body of the bottom plate. The reinforcing beam effectively enhances the overall structural strength of the bottom plate and improves the compression and impact resistance of the bottom plate. Fixing holes are provided on the reinforcing beam, and the fixing holes are dispersed at the bottom of the battery pack. A crossbeam connected to the frame is provided at the bottom of the vehicle. The crossbeam is located at the bottom of the battery pack and the distribution of the crossbeam and the fixing holes corresponds to that of the crossbeam. During specific installation, the battery pack is placed on the crossbeam and connected and fixed to the crossbeam. The crossbeam provides structural support for the battery pack. The crossbeam and the reinforcing beam jointly enhance the structural strength of the battery pack. The crossbeam also has a bottom protection function for the battery pack, which can effectively buffer some impacts and improve the safety of the battery pack.

[0009] 3. When the battery pack needs maintenance or replacement due to a fault, the bottom fixation of this solution provides a larger operating space for installation or removal compared to the side fixation, making the work more convenient, reducing the difficulty of operation caused by the close fit between the battery pack and the vehicle body, effectively improving work efficiency and shortening maintenance time.

[0010] Furthermore, the reinforcing beam is arranged in the liquid cooling area of ​​the base plate body, and the reinforcing beam is connected to the inner walls of the upper and lower sides of the base plate body along the thickness direction.

[0011] Setting the reinforcing beam inside the bottom plate body effectively increases the overall structural strength of the bottom plate, enhances the impact resistance of the bottom of the battery pack, and ensures the stability of the internal structure of the battery pack.

[0012] Furthermore, the reinforcing beam on the side bottom plate is arranged on a side of the side bottom plate away from the middle bottom plate and is located outside the liquid cooling area.

[0013] The above arrangement provides fixing holes on the outermost side of the base plate body, and the fixing points between the bottom of the battery pack and the crossbeam at the bottom of the frame are more dispersed. When the battery pack is subjected to force, the stress is dispersed more evenly, and the connection between the battery pack and the frame is more stable.

[0014] Furthermore, a plurality of vertical partitions are evenly arranged along the length direction in the hollow cavity of the middle bottom plate and the side bottom plate. The reinforcing beams in the middle bottom plate act as vertical partitions, which divide the liquid cooling area into a plurality of cooling channels. The plurality of cooling channels in the middle bottom plate or the side bottom plate are interconnected.

[0015] The design of the above-mentioned vertical partitions not only guides the flow direction of the coolant, but also enhances the structural strength and stability of the base plate, preventing deformation or damage caused by external force impact during transportation or installation, which may cause the coolant in the base plate to leak and affect the performance of the battery pack.

[0016] Furthermore, the vertical partition located in the middle position of the middle bottom plate is a partition partition, and all the vertical partitions in the bottom plate body, the reinforcing beams in the middle bottom plate, and the two ends of the side walls where the middle bottom plate contacts the side bottom plates are all located inside the hollow cavity. The end of the partition partition facing the front panel protrudes from the other vertical partitions and divides the liquid cooling area into an inflow cavity and an outflow cavity.

[0017] The above arrangement enables the inflow cavity and the outflow cavity in the base plate body to be separated at one end and connected at the other end, which facilitates the coolant to flow along a U-shaped path in the base plate body, so that it has a longer residence time during the flow process, increases the heat exchange area and time with the battery, improves the heat exchange efficiency, and ensures efficient heat dissipation.

[0018] Furthermore, the bottom plate body is provided with a water inlet and a water outlet at one end close to the front panel, and the water inlet and the water outlet are respectively communicated with the inflow cavity and the outflow cavity.

[0019] Concentrating the coolant inlet and outlet at one end of the base plate allows the coolant to flow along a U-shaped path within the base plate, which is conducive to precisely controlling the flow and direction of the coolant. This reduces the complexity of the internal flow channel design while ensuring the length and area of ​​the heat exchange path. The centralized design of the inlet and outlet facilitates subsequent maintenance and overhaul. When the system needs to be cleaned, inspected, or parts replaced, staff can quickly locate them, reducing the impact on other parts of the battery pack and improving maintenance efficiency.

[0020] Furthermore, a mounting beam is installed on the upper surface of the base plate body, and the two ends of the mounting beam are respectively connected and fixed to the left and right beams. A bulge is formed upward in the middle of the mounting beam, and the mounting beam has multiple bolt holes on both sides of the bulge. The bolt holes are located directly above the reinforcing beam, and threaded connection holes corresponding to the bolt holes are provided on the base plate body.

[0021] In the above setting, the mounting beam enhances the fixation of the internal battery cell module, ensuring the stability of the battery cell module in the battery pack, and the bolts passing through the bolt holes on the mounting beam and the threaded connection holes on the base plate body effectively enhance the connection strength between the mounting beam and the base plate body, ensuring the structural strength of the box.

[0022] Furthermore, bolt sleeves are provided at positions corresponding to the fixing holes on the bottoms of the front panel, the rear panel and the mounting beam, and the bolt sleeves are located in the fixing holes.

[0023] The above arrangement ensures that when the bolts and bolt sleeves are fixing the battery pack, the bolts are connected to the front panel, rear panel and mounting beam in addition to the base plate body, making the connection between the battery pack as a whole and the crossbeam at the bottom of the frame more firmly. The battery pack can adapt to more complex and harsh environments, and the overall performance of the battery pack is more stable.

[0024] Furthermore, the bottom plate body is provided with blocking blocks at both ends in the length direction, and sealing materials are provided at the connection between the blocking blocks and the bottom plate body.

[0025] The purpose of the above setting is to seal the liquid cooling area in the bottom plate to ensure that the internal coolant does not leak and to ensure the normal operation of the liquid cooling system and the battery pack.

[0026] The present utility model also provides another technical solution: a box body of a liquid-cooled battery pack, including an upper box cover and a bottom plate, the upper box cover and the bottom plate are connected and fixed by bolts, bolts are installed in the fixing holes on the bottom plate, and the box body is connected and fixed to a crossbeam arranged at the bottom of the vehicle and connected to the frame by the bolts.

[0027] Beneficial effects:

[0028] The bolts pass through the fixing holes and cooperate with the bolt sleeves inside them to connect and fix the box to the crossbeam at the bottom of the vehicle. The above arrangement not only reduces the battery pack's occupation of the vehicle's Y-direction space, but also the crossbeam at the bottom of the box supports the battery pack as a whole, avoiding the situation in which the bottom of the battery pack is suspended in the air due to the side fixing strategy of the battery pack in the existing technical solution, reducing the stress and distortion caused by the suspended bottom of the battery pack without support, and making the internal structure and performance of the battery pack more stable. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic diagram of the bottom plate structure of Example 1 of the present utility model.

[0030] Figure 2 This is a bottom view of the base plate structure of Example 1 of the present utility model.

[0031] Figure 3 This is a structural diagram of the base plate body of Example 1 of the present utility model.

[0032] Figure 4 This is a schematic diagram of the structure inside the base plate body of Example 1 of the present utility model.

[0033] Figure 5 This is a schematic diagram of the flow path of the coolant in the base plate body of the first embodiment of the present invention.

[0034] Figure 6 This is a schematic diagram of the explosion structure of Example 2 of the present utility model.

[0035] Figure 7 This is a bottom view of the second embodiment of the present invention. DETAILED DESCRIPTION

[0036] The following is further described in detail through specific implementation methods:

[0037] The figure marks in the drawings of the specification include: bottom plate 1, upper box cover 2, bottom plate body 3, middle bottom plate 31, side bottom plate 32, front panel 4, rear panel 5, left beam 6, right beam 7, reinforcing beam 8, fixing hole 9, protective plate 10, mounting beam 11, bolt hole 12, threaded connection hole 13, vertical partition 14, bolt sleeve 15, blocking block 16, water inlet 17, water outlet 18, partition partition 19.

[0038] Example 1:

[0039] like Figure 1-Figure 5 As shown, a bottom plate of a liquid-cooled battery pack includes a bottom plate body 3 and a front panel 4, a rear panel 5, a left beam 6, and a right beam 7 welded and fixed to the upper surface of the bottom plate body 3. The front panel 4 and the rear panel 5 are L-shaped structures facing each other. The cavity surrounded by the front panel 4, the rear panel 5, the left beam 6, the right beam 7 and the bottom plate body 3 is used to accommodate the battery cell module; the bottom plate body 3 includes a middle bottom plate 31 and side bottom plates 32 located on both sides of the middle bottom plate 31. In this embodiment, the two middle bottom plates 31 each have a side bottom plate 32, and the two side bottom plates 32 are symmetrically arranged and have the same structure; the interior of the middle bottom plate 31 and the two side bottom plates 32 are both hollow cavities, and the hollow cavity serves as the liquid cooling area of ​​the battery pack. When the battery pack is working, coolant flows in the liquid cooling area.

[0040] A plurality of reinforcing beams 8 are provided on the bottom plate body 3 along its length direction. The reinforcing beams 8 are provided with fixing holes 9. The opening direction of the fixing holes 9 is toward the side away from the cavity. The fixing holes 9 are installed with fastening components for fixing the battery pack box. Preferably, as Figure 4As shown, in this embodiment, the reinforcing beam 9 is set in the liquid cooling area of ​​the bottom body 3, and the reinforcing beam 9 is connected to the inner wall of the upper and lower sides of the bottom plate body 3 along its thickness direction, so as to enhance the overall structural strength of the bottom plate 1 and the impact resistance of the battery pack bottom, and reduce the impact damage inside the battery pack; further, the reinforcing beam on the side bottom plate 32 is set on the side of the side bottom plate 32 away from the middle bottom plate 31, and is located outside the liquid cooling area, so as to achieve a dispersed distribution of the fixing holes 9 on the bottom plate, so that the stress distribution of the battery pack is more uniform when the battery pack is subjected to force, and the connection stability between the battery pack and the frame is enhanced. Figure 2 As shown, in order to reduce the friction and wear between the bolt assembly and the base plate body 3, a protective plate 10 is provided on the lower surface of the base plate body 3 at a position corresponding to the reinforcing beam 8.

[0041] Through the above arrangement, the fixing holes 9 of the battery pack are arranged at the bottom of the base plate 1. On the one hand, the battery pack occupies less space in the Y direction of the vehicle and reduces the interference of the battery pack with the installation of other components or systems. At the same time, the volume of the battery cells that can be accommodated inside the battery pack is increased, so that the overall energy of the battery pack is increased, and the volume energy density is increased, which is beneficial to improving the endurance of the whole vehicle. On the other hand, the fixing holes 9 of the battery pack are dispersedly arranged at the bottom of the base plate 1 and connected to the crossbeam arranged at the bottom of the frame, so that the bottom of the battery pack has support to avoid being suspended, and the support points at the bottom of the battery pack are evenly distributed, so that the overall force of the battery pack is more dispersed, and the distortion of the battery pack caused by the concentrated force is reduced.

[0042] like Figure 1-Figure 3 As shown, a mounting beam 11 is installed on the upper surface of the base plate body 3, and the two ends of the mounting beam 11 are respectively connected and welded to the left and right beams 7. A bulge is formed upward in the middle of the mounting beam 11, and the mounting beam 11 has multiple bolt holes 12 on both sides of the bulge. The bolt holes 12 are located directly above the reinforcing beam 8, and the base plate body 3 is provided with threaded connection holes 13 corresponding to the bolt holes 12. In addition to welding, the mounting beam 11 and the base plate body 3 are fixed together, and the bolts, bolt holes 12 and threaded connection holes 13 cooperate to enhance the connection strength between the mounting beam 11 and the base plate body 3.

[0043] like Figure 2 As shown, to further enhance the structural strength of the battery pack, fixing holes 9 are longitudinally extended through the base plate body 3. Bolt sleeves 15 are provided at the bottoms of the front panel 4, rear panel 5, and mounting beam 11 at positions corresponding to the fixing holes 9. Bolt sleeves 15 are located within the fixing holes 9. This arrangement ensures that when the bolts and bolt sleeves 15 secure the battery pack, they are connected not only to the base plate body 3 but also to the front panel 4, rear panel 5, and mounting beam 11. This ensures a more secure connection between the battery pack and the crossbar at the bottom of the vehicle frame, allowing the battery pack to adapt to more complex and harsh environments and achieving more stable overall performance.

[0044] like Figure 4 、 Figure 5 As shown in the figure, a plurality of vertical partitions 14 are evenly arranged in the hollow cavity of the middle bottom plate 31 and the side bottom plate 32 along the length direction. The reinforcing beam 8 in the middle bottom plate 31 also serves as the vertical partition 14. The vertical partition 14 divides the liquid cooling area into a plurality of cooling channels. The plurality of cooling channels in the middle bottom plate 31 or the side bottom plate 32 are interconnected. Among them, the vertical partition 14 in the middle position of the middle bottom plate 31 is a partition partition 19. All the vertical partitions 14 in the bottom plate body 3, the reinforcing beam 8 in the middle bottom plate 31, and the two ends of the side wall of the middle bottom plate 31 in contact with the side bottom plate 32 are located in the middle. Inside the cavity, the end of the partitioning baffle 19 facing the front panel 4 protrudes beyond the other vertical baffles 14, dividing the liquid cooling zone into an inflow chamber and an outflow chamber. The base plate body 3 is provided with a water inlet 17 and a water outlet 18 at the end near the front panel 4, communicating with the inflow chamber and the outflow chamber, respectively. The base plate body 3 is provided with sealing blocks 16 at both ends of its length. The sealing block 16 on the front panel 4 side contacts the partitioning baffle 19, separating the front ends of the inflow chamber and the outflow chamber. A flow channel gap is left between the sealing block on the rear panel 5 side and the vertical baffles 14 and the reinforcing beam 8. To ensure the sealing of the liquid cooling zone, sealing material is provided at the connection between the sealing block 16 and the base plate body 3.

[0045] Through the above arrangement, the inflow cavity and the outflow cavity in the bottom plate body 3 are separated from each other, and a connecting flow channel is provided at one end of the bottom plate body 3 facing the rear panel 5, so that the coolant flows along the liquid cooling area in the bottom plate body 3. Figure 5 The U-shaped path shown by the middle arrow flows. The U-shaped flow path allows the coolant to have a longer residence time during the flow process, increases the heat exchange area and time, improves the heat exchange efficiency, and ensures efficient heat dissipation. At the same time, the setting of the vertical partition 14 not only guides the flow direction of the coolant, but also enhances the structural strength and stability of the base plate 1, prevents deformation or damage caused by external force impact during transportation or installation, ensures the sealing of the liquid cooling system, and ensures that the coolant will not leak.

[0046] Example 2

[0047] like Figure 6 、 Figure 7As shown, a liquid-cooled battery pack housing includes an upper housing cover 2 and the bottom plate 1 of Example 1. The upper housing cover 2 and the bottom plate 1 are fixed together by bolts. During installation, a crossbeam connected to the vehicle frame is provided at the bottom of the vehicle. The crossbeam is located at the bottom of the housing. Threaded through holes corresponding to the fixing holes 9 are formed on the crossbeam. Bolts are installed in the fixing holes 9. The bolts pass through the threaded through holes and connect with the bolt sleeves 15 in the fixing holes 9, thereby connecting and fixing the housing and the crossbeam, and the battery pack is completely fixed. This arrangement not only reduces the Y-axis space occupied by the battery pack, but also the crossbeam at the bottom of the frame supports the battery pack as a whole, avoiding the situation in which the bottom of the battery pack is suspended in the air due to the side fixing strategy of the battery pack in the existing technical solution. This reduces the stress and distortion caused by the suspended bottom of the battery pack without support, and makes the internal structure and performance of the battery pack more stable.

[0048] The above description is merely an embodiment of the present invention, and the commonly known specific technical solutions and / or features of the solution are not described in detail here. It should be noted that for those skilled in the art, without departing from the technical solution of the present invention, several variations and improvements can be made, which should also be considered as the scope of protection of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection claimed in this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A bottom plate of a liquid-cooled battery pack, characterized in that: The bottom plate body comprises a base plate main body and front and rear panels and left and right side beams fixed on the upper surface of the base plate main body. The cavity surrounded by the front and rear panels and the left and right side beams below the base plate main body is used to accommodate the battery cell module. The base plate main body comprises a middle base plate and side base plates located on both sides of the middle base plate. The side base plates are connected and fixed to the left and right side beams. The interiors of the middle base plate and the side base plates are both hollow cavities, which serve as the liquid cooling area of ​​the battery pack. A plurality of reinforcing beams are provided on the base plate main body along its length direction. The reinforcing beams are arranged in the liquid cooling area of ​​the base plate main body. The reinforcing beams are connected to the inner walls of the upper and lower sides of the base plate main body along the thickness direction. The reinforcing beams on the side base plates are arranged on the side of the side base plate away from the middle base plate and outside the liquid cooling area. A fixing hole is opened on the reinforcing beam, and the opening direction of the fixing hole is toward the side away from the cavity. A cooling flow channel is provided in the liquid cooling area, and the base plate main body is provided with blocking blocks at both ends in the length direction.

2. The bottom plate of a liquid-cooled battery pack according to claim 1, characterized in that: A plurality of vertical partitions are evenly arranged in the length direction of the hollow cavity of the middle bottom plate and the side bottom plate. The reinforcing beams in the middle bottom plate serve as vertical partitions. The vertical partitions divide the liquid cooling area into multiple cooling channels. The multiple cooling channels in the middle bottom plate or the side bottom plate are interconnected.

3. The bottom plate of a liquid-cooled battery pack according to claim 2, characterized in that: The vertical partition located in the middle position of the middle bottom plate is a partition partition. All vertical partitions in the bottom plate body, the reinforcing beams in the middle bottom plate, and both ends of the side walls where the middle bottom plate contacts the side bottom plates are all located inside the hollow cavity. The end of the partition partition facing the front panel protrudes from the other vertical partitions and divides the liquid cooling area into an inflow cavity and an outflow cavity.

4. The bottom plate of a liquid-cooled battery pack according to claim 3, characterized in that: The bottom plate body is provided with a water inlet and a water outlet at one end close to the front panel, and the water inlet and the water outlet are respectively communicated with the inflow cavity and the outflow cavity.

5. The bottom plate of a liquid-cooled battery pack according to claim 4, characterized in that: A mounting beam is installed on the upper surface of the base plate body, and the two ends of the mounting beam are respectively connected and fixed to the left and right beams. A bulge is formed upward in the middle of the mounting beam, and a plurality of bolt holes are opened on both sides of the bulge. The bolt holes are located directly above the reinforcing beam, and threaded connection holes corresponding to the bolt holes are provided on the base plate body.

6. The bottom plate of a liquid-cooled battery pack according to claim 5, characterized in that: The bottoms of the front panel, the rear panel and the mounting beam are provided with bolt sleeves at positions corresponding to the fixing holes, and the bolt sleeves are located in the fixing holes.

7. The bottom plate of a liquid-cooled battery pack according to claim 6, characterized in that: A sealing material is provided at the connection between the blocking block and the base plate body.

8. A liquid-cooled battery pack housing, characterized in that: The box body comprises an upper box cover and a bottom plate as described in any one of claims 1 to 7, wherein the upper box cover and the bottom plate are fixed by bolts, bolts are installed in the fixing holes on the bottom plate, and the box body is connected and fixed to a crossbeam provided at the bottom of the vehicle and connected to the frame by bolts.

Images